A picture taken on October 23, 2012 shows the screen of a blackberry phone reading the name of micro-blogging site Twitter below its logo. AFP PHOTO FRED TANNEAU (Photo credit should read FRED TANNEAU/AFP/Getty Images)

By Annie Hauser

When Rebecca Regnier, 43, wants more accountability for her weight-loss efforts, she turns to a few thousand of her closest friends — on Twitter.

The Michigan-based TV host and author started tweeting about weight loss in 2008 for little extra accountability. "I enjoyed weekly Weight Watchers meetings, but I felt I had more to say [about weight loss]," she says. "Dieting can be such a serious topic that every once in a while you have to laugh about it, and I wanted to connect with people who might enjoy a laugh or two."

Thanks to the 24/7 social support, connecting with like-minded dieters online really works, researchers from the University of South Carolina's Arnold School of Public Health report in the journal Translational Behavioral Medicine. This is one of the first studies to measure Twitter's direct impact on dieting.

In Regnier's case, she says tweeting helped her lose 20 pounds and keep it off since 2010. She's such a fan that she even wrote a book about it, Your Twitter Diet, which shows other people how to drum up weight-loss support online. (She also blogs at DoesThisBlogMakeUsLookFat.com.)

"I give help and I get help via the support of Twitter," she explains. "Celebrities have a team of people, and I always say that Twitter can be that for you. Your own army of support when you need it."

Regnier is not the only one who has used Twitter to stay accountable for weight loss. Sen. Claire McCaskill of Missouri made headlines in 2011 for tweeting her diet and exercise routines. The senator has since lost 50 pounds. New York Times reporter Brian Stelter lost 90 pounds by tweeting every bite in 2010.

How Tweeting Helps Weight Loss

In the USC study, 96 overweight or obese adults were randomly assigned to either listen to two podcasts per week about nutrition and fitness or to listen to the podcasts, record physical activity, and connect with other study participants on Twitter. At the end of the six-month period, the Twitter users lost more weight — each tweet actually corresponded with half a pound lost, researchers found, suggesting that social networking can be a powerful, accessible tools for dieters.

"Traditional behavioral weight loss interventions generally provide social support through weekly, face-to-face group meetings. While we know this is effective, it is costly and can create a high degree of burden on participants," said lead researcher Brie Turner-McGrievy, PhD, MS, RD, in a release. "Providing group support through online social networks can be a low cost way to reach a large number of people who are interested in achieving a healthy weight."

Now that Regnier is at her happy weight, she uses Twitter to communicate her new goals: gaining strength and running longer distances. Plus, she finds it's a good pick-me-up when she slips out of her usual healthy eating routine. "There's no weight loss 'before and after' for me — I'm always in the 'during' process," she says. "If I slip on my diet one afternoon, people are very sweet to me, and remind me that one afternoon doesn't have to make my whole week."

Ready for your own online support group? Regnier has these tips to help you find the support you need for weight loss success:

- State your intention. Publicize your goals on Twitter, Regnier says. It makes them more concrete, and keeps you accountable.

- Make Twitter work for you. Whether you choose to tweet everything you eat or only post when you need a little extra support, there are different ways to approach your diet online. It's also important to celebrate your successes on Twitter, Regnier says. "You'll practice what you preach when you preach it online," she says.

- Find what you like. Whether you're eating Paleo, training for your first 5K, or counting calories, seek out people and organizations with the same health goals. Bloggers, experts, and organizations with like interests can be great sources for inspiration, support, recipes, workout plans, and more.

- Be generous and get involved. Use Twitter search to find conversations and people who are interesting to you, and don't be afraid to jump in. "When you see something good, share it," Regnier says. "Open yourself up to being generous. It’s like you’re at a dinner party — try to be the person you want to sit next to."

- Don't forget about safety. "I always caution people that Twitter is social, and it is public," Regnier says. "If you wouldn't say it to your pastor, police, or parents, don't say it online."

- Try other online outlets. Free online nutrition and fitness challenges are everywhere; it's just a matter of finding one that appeals to you. Some websites, such as DietBet.com, allow users to wager real money on their weight-loss efforts if you're looking for a more serious competition.